OFFSET
0,2
COMMENTS
Linear recurrence and g.f. confirmed by Shutov/Maleev link in A301718. - Ray Chandler, Aug 30 2023
LINKS
Ray Chandler, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (2, -1, 0, 0, 1, -2, 1).
FORMULA
From Colin Barker, Apr 09 2018: (Start)
G.f.: (1 + x)^2*(1 + 2*x + x^2 + 2*x^3 + x^4) / ((1 - x)^3*(1 + x + x^2 + x^3 + x^4)).
a(n) = 2*a(n-1) - a(n-2) + a(n-5) - 2*a(n-6) + a(n-7) for n>6. (End)
Conjecture: a(n) ~ 14*n^2/5. - Stefano Spezia, Mar 28 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Mar 26 2018
STATUS
approved